to starting pelvic RT, and very high ovarian survival rates. 13,14 Studies have shown that in women under age 40 who underwent laparoscopic ovarian transposition, ovarian function preservation rates were as high as 88.6%. 15 There are no consensus guidelines on dose constraints to transposed ovaries, and ideally, the dose to the transposed ovary or ovaries should be as low as possible. However, one study looking at women treated with intensity-modulated radiation therapy aſter ovarian transposition showed that dose constraints of a maximum dose < 9.985 Gy, mean dose < 5.32 Gy, and V5.5 < 29.65% to the transposed ovary could be better at preventing ovarian dysfunction, especially in women under age 38. 16 CT simulation can typically be performed within a week of the procedure if the abdominal wall has sufficiently deflated (aſter surgical insufflation with laparoscopy) for reproducible treatment planning and delivery. The surgeon should mark the location of the transposed ovary or ovaries with a surgical clip and the ovarian tissue should be contoured for dosimetric evaluation. If the ovary is high enough in the abdomen, there should be minimal direct dosing to the ovary; however, the ovary will likely still receive some radiation exposure via internal scatter. This is important to explain when counseling patients, as the risk of ovarian failure remains given the tissue’s sensitivity to radiation. Other risks associated with ovarian transposition include complications at the time of surgery, ovarian torsion, vascular injury, fallopian tube infarction, and small bowel obstruction due to postsurgical adhesions. Ovarian cyst formation is common and reported in up to 95% of patients but is unlikely related to the transposition procedure. Patients who undergo successful ovarian transposition with function retained aſter radiation therapy may retain viable eggs aſter treatment, which can later be retrieved for in vitro fertilization procedures. Ovarian transposition tends to be more successful in younger women, with the best outcomes seen in patients under age 35 (preservation rates by age: 25-30: 87.5%; 31-35: 62.5%; and 35-40: 42.9%). 17 National guidelines by the American Society of Clinical Oncology and the National Cancer Comprehensive Network 3,18 both recommend offering ovarian transposition to appropriately selected AYA cancer patients (Table 2) and referral to psychosocial providers when patients are distressed about potential infertility. Premature Ovarian Insufficiency Although fertility is an important consideration, the implications of POI or premature menopause on a young woman’s health can oſten be overlooked by providers. Premature ovarian insufficiency is age dependent, with doses of 16.5 Gy at age 20 vs 10 Gy at age 45 to deplete the ovarian oocyte pool with conventional fractionation of 1.8-2.0 Gy per fraction. The shutdown of ovarian tissue with low doses of RT leads to decreased production of estrogen. Estrogen has many important normal functions in the body unrelated to reproductive health, including maintaining bone mineral density, decreasing the risk of cardiovascular disease by lowering the risk of atherosclerosis, neuroprotective effects due to estrogen-dependent DNA repair mechanisms in the brain, as well as effects on cognition and the immune system. The decreased Figure 1. A typical pelvic radiation therapy plan using intensity-modulated radiation therapy, with ovaries identified on CT. Pelvic RT and AYA Female Patients CME REVIEW September 2023 Applied Radiation Oncology 7